Electric car-recording block-signal.



"1101295575. PATENTED AUG. 11, 1908.

. W. J. MURRAY.

ELECTRIC GAR RECORDING BLOCK SIGNAL.

APPLIOATION FILED APE. 16,1907.

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PATENTED AUG. 11, 1908.

W. J. MURRAY. ELECTRIC CAR RECORDING BL OCK SIGNAL.

APPLICATION FILED APR. 16,1907.

3 SHEETS-SHEET 2.

6 90. H. A .WWAWAWNANW 5 A 'No. 895,575. PATENTBD AUG. 11, 1908. W. J.MURRAY.

ELECTRIC OAR RECORDING BLOCK SIGNAL.

APPLICATION FILED APR. 16,1907.

3 SHEETSSHEET 3.

5 E] I W 67 ll] 76 t 26 6 l g 43 k 2.9 v q a 6 G v k I 27/2 5 5 39 eacjmw/m W UNITED STATES PA TENT oFFreE.

WILLIAM J. MURRAY, OF LEAVENWORTH, KANSAS, ASSIGNOR OF ONE-HALF TOHERBERT W. WOLCOTT', OF LEAVENWORTH, KANSAS.

ELE C'IRIC CAR-RE CORD ING B LOCK-SIGNAL.

in connection with electric street and interurban car lines, and myobject is to produce means whereby the entrance of a car into a blockshall result in the operation of the signal to notify those in charge ofcars approaching the opposite end of the block that the block isoccupied and shall also afiect the signal mechanism so that a carsubsequently entering the block from the same end as the car therein,shall not affect the signal unless the preceding car has first passedout of the block and restored the signal to normal condition.

A further object is to produce means whereby a car entering the occupiedblock from the opposite end from that entered by the car therein, shallnot affect the signal mechanism and that the latter shall likewise beunaffected if said second car backs out of the block onto the same trackor siding from which it entered.

A still further object is to produce a signal mechanism which willpermit of the entrance of a predetermined number of carsseven in thisinstance-traveling in the same direction, into the block Without any ofthem affecting the signal except the first, but which in the event thatanother car traveling in the same direction enters the block, willreverse the si nal, that is will show clear at the end of the blocktoward which said cars are traveling and danger at the end at which saidoars entered.

A still further object is to produce a signal mechanism which in theevent of the entrance of a car into the block from the opposite endwhile the block is occupied by such eight cars and when therefore thesignal is safety will result in reversing the signal in front of saidentering car from safety to danger in order to Warn those in charge ofthe car to back out of the block until the cars therein have all passedout and have by suc- Specification of Letters Patent.

Application filed April 16, 1907.

Patented Aug. 11, 1908.

Serial No. 368,587.

cessively influencing the mechanism, eventually restored the signal tonormal or clear condition.

To these ends the invention consists in certain novel and peculiarfeatures of construction and organization as hereinafter described andclaimed; and in order that it may be fully understood reference is to behad to the accompanying drawings, in which- Figure 1, is a plan view ofthe main relays and the circuit making and breaking mechanism actuatedthereby. Fig. 2, is a side view of the same with a part broken away.Fig. 3, is a section on the line IIIIII of Fig. 2. Fig. 4, is anenlarged section on the line IV Fig. 1. Fig. 5, is a section on line VVof Fig. 1. Fig. 6, is a central longitudinal section of one of theconductors in circuit with the trolley wires at the opposite end of theblock. Fig. 7 is a section 011 the line VIIVII of Fig. 6. Fig. 8, is acentral vertical longitudinal section of the preferred type ofconstruction of the device shown in Fig. 6. Fig. 9, is an end view ofthe same. Fig. 10, is a diagrammatic view of a block and the signalmechanism therefor. Figs. 11 and 12, are diagrammatic views of modifiedforms.

Referring first to the main relay construction, 1 indicates a bed ofwood or its equivalent, and 2 and 3 similar electro-magnets or relaysmounted thereon.

4 and 5 indicate res ectively the armatures for such relays and 6 everscarrying said armatures and mounted upon suitable brackets 7, thearmatures being normally held yieldingly away from the relays by springsS mounted on rods 9 secured in any suitable manner to the bed 1 andextending through the levers as guides therefor, nuts 10 being securedto the upper ends of said rods 9 to prevent the springs moving thearmatures too far from the relays.

11. and 12 indicate pawls depending ivotally from the ends of the leversof re ays 2 and 3 respectively, the lower ends of said pawls fitting andhaving play in substantially tubular guide arms "13 projecting from thecaps 14 which in conjunction with blocks 15 form bearings for thetransverse shaft 16, said shaft being equipped with a toothed wheel 17engaged by a detent or resilient brake 18 for the purpose of preventingthe shaft from being turned accidentally or from being turned more thana predetermined distance.

19 and 20 indicate ratchet wheels secured rigidly upon opposite ends ofshaft 16 and having their teeth disposed in opposite directions, saidratchet wheels being arranged vertically below pawls 11 and 12respectively, in order that the energization of one of said magnetsshall result in causing the pawls actuated thereby to engage itsrespective ratchet wheel and rotate shaft 16 one step, the direction ofrotation being according to which relay is energized.

21 and 22 indicate cams secured rigidly on shaft 16, said cams beingapproximately semicircular in form and so disposed that when in normalosition,that is when the block is unoccup1edthey present, When viewedfrom the side, a V-shapedopening as shown by Fig. 5, such opening beingoccupied by l the anti-friction rollers 23 carried by the switches 24and 25 hinged as at 26 to a standard 27 mounted on the bed, switches 24and 25 being arranged respectively in the vertical planes of the cams 21and 22.

The outer ends of the switches are preferably provided with cups 28carrying carbons or other good contacts 29 for engagement with othergood contacts 30 fitting slidingly in sleeves 31 and held yieldinglydepressed therein by springs 32 hearing at their upper ends againstspring cotters 33 carried by the sleeves, the conductors 30 having theirlower ends reduced to provide shoulders 34 to rest upon the inwardlyflanged lower ends 35 of the sleeves when such contacts are not engagedby their respective contacts 29. The sleeves are carried by contactplates 36 and 37 mounted upon an insulating standard 38, and secured inany suitable manner to the bed contiguous to standard 38 is a support 39for switches 24 and 25 when occupying their depressed or inoperativepositions.

40.and 41 indicate trolley wires at opposite ends of the block for carstraveling toward the latter, and 42 the trolley wire of the blockconnecting trolley wires 40 and 41, said trolley wire 42 being alsoconnected to the trolley wires 43 and 44 at op osite ends of the blockfor cars leaving the atter.

Conducting appliances for each of the wires 40, 41, 43 and 44 arepreferably constructed as follows :45 indicates a wood or otherinsulating bar of suitable length provided in its upper side with alongitudinal groove 46 opening at each end in a bifurcation in the endof the bar. 47 and 48 inclicate parallel angle plates secured to theunderside of bar 45 at opposite sides of its bifurcations, the innerarms of said angle plates terminating in upwardly and outwardly flaredends 49 for a purpose hereinafter explained. The bars 45 are fittedagainst the underside of the trolley wires at the proper points so thatthe latter shall extend through grooves 46. Wedges 50 are then driveninto the ends of the bifurcations above the wires to produce the arch inthe wire shown by Fig. 8, the wedges having upwardly disposed shoulders51 to bear against the underside of bar 45, and longitudinal grooves 52in their tapered undersides to re ceive the wires and guard againstlateral movement thereof as shown in Fig. 9. After the wires are thussecured to the bars as explained, the latter are secured to theoverlying cap boards 53 supported in any suitable manner above thenormal plane' of the trolley wire, said capboards being preferablyprovided with longitudinal grooves 54 which mate with grooves 46 andform passages for the trolley wires. 55 are conductors connecting thetrolley wires with conductors 56, which conductors in turn are connectedb conductors 57 to the angle plates 47. It will thus be seen that thetrolley wires are always electrically connected to angle plates 47 andare adapted at times to be electrically connected by the trolley wheels48 as hereinafter explained, to the angle plates 48 of the conductingappliances. The trolley wire 40 is connected by conductor 58 to acontact post 59, which post when the block is unoccupied is electricallyconnected by a spring-actuated bar 60 to a second contact post 61.connected by conductor 62 to relay 2. The angle plate 48 of theconducting appliance of trolley wire 41 is connected by conductor 63 tocontact post 64, which when the block is not occupied by a car isconnected by a spring actuated bar 65 with a contact post 66 con nectedby conductor 67 with relay 3, the re lays 2 and 3 being grounded byconductor 68,

and in order to avoid danger of burning out said relays, lamps 69 orother resistance devices are connected up in series with the relays. 70indicates a conductor leading from trolley wire 43 to the switches 24and 25. 71 is a conductor electrically connecting plate 36 with theground wire 72, and arranged on said conductor 71 near one end of theblock is a danger signal either of the audible or visual type or both,that shown, being a series of red lamps 73. An electro magnet 74 is alsoin circuit with said wire and adapted when energized to attract itsarmaturebar 65 and break the circuit between contacts 64 and 66 as shownin Fig. 10. Also located on said conductor 71 at or near the oppositeend of the block is a safety signal which like the other may be of anydesired type or plurality oftypes, the signal shown preresenting aseries of white lamps 7 76 indicates a conductor electrically connectingplate 37 with the groundpreferably through ground conductor 7 2, and incircuit with said conductor 76 at the same end of the block as thedanger signal 73 is a safety signal, shown as white lamps 77. Also incircuit with conductor 76 is an electro-mag net 78 which is adapted whenenergized to attract its armature bar 60 and thus break the circuitbetween contact posts 59 and 61. Also in circuit with said conductor 76and at the same end of the block as the safety signal 75 is a dangersignal, preferably in the form of a plurality of red lamps 79. 80 is aconductor connecting the angle plate 48 of trolley wire 43 with relay 3and 8,1 is a conductor connecting the angle plate 48 of trolley wire 44with relay 2, it being noticed that the drawing shows conductors 80 and81 connecting conductors 67 and 62 respectively.

In Figs. 6 and 7 which represent a modification of the conductingappliance detailed in Figs. 8 and 9, 82 indicates a board equipped atits underside with parallel angle plates 47 and 48 and with alongitudinal rib 83 which increases in thickness toward its ends and isprovided with a longitudinal groove 84 in its lower edge to receive thetrolley wire as shown, the trolley wire being arched to correspond withthe lower edge of the rib. The trolley wire is also connected byconductors 55, 56 and 57 with angle plate 47 as shown by Figs. 8 and 9.

In practice, as a trolley wheel passes under one of the conductingappliances, the wheel W comes into engagement with angle plates 47 and48 and by reason of the arch in the contiguous portion of the wire rideswholly on said angle plates for part of their length so as to insure apositive connection therewith, the circuit through the motor or motorsof the car being undisturbed because the trolley wire is electricallyconnected to the contact plate 47 upon which the trolley wheel rolls.

WVhen the block is unoccupied, the signal device, or lamps is turned offand consequently contacts 60 and 65 are respectively engaged withcontact posts 59, 61, 64 and 66, thelamps being turned off because theantifriction rollers 23 are engaging the inoperative faces of the cams21 and 22, at which times switches 24 and 25 are out of engagement withcontacts 30. Now as the trolley wheel of a car traveling in thedirection indicated by the arrow, Fig. 10, comes into engagement withangle plate 48 of the conducting appliance of trolley wire 40, a currentpasses from said angle plate through 58, 59, 60, 61, 62 and 2, to theground through conductor 68 and the resistance device 69. The completionof this circuit results in the energization of relay 2 and theattraction of its armature and consequently through the medium of itslever 6 and pawl 11, effects the retation of shaft 16 to the extent ofone step in the direction indicated by the arrow, Fig. 2, the resultbeing cam 21 raises switch 24 until its contact 29 engages its companioncontact 30 and thus completes a circuit as follows from trolley wire 43,through conductor 7 (1,

switch 24, plate 36, and conductors 71 and 72 to the ground, thecompletion of this circuit turning lamps 73 and on so as to display thedanger signal at the remote end and the safety signal at the contiguousend of the block. Such current also energizes magnet 74 and attracts itsarmature 65 and breaks the circuit between contact post 64 and 66. As aresult of the breaking of this circuit a car entering the block from theopposite end fails to energize relay 3 and therefore does not affectsignal 73 or 75 nor operate signals 77 and 79, it being obvious in thisevent that the duty of the person in control of the car is to back itout of the block and wait until the latter is clear.

As a seco'ndcar enters the block from the end where the safety signal isdisplayed it likewise fails to affect the signals but completes acircuit through trolley wire 40 conductor 58, 59, 60, 61, and 62, relay2, lamp 69, conductor 68 to ground, the energization of relay 2 turningshaft 16 one step in the same direction as before, cam 21 revolving asecond step without affecting the position of switch 24 and thereforewithout breaking the circuit through signals 73 and 75. As the parts arethus arranged six additional carseight in allmay enter the block fromthe same end, the eighth car entering causing cam 21 to make the eighthstep. As this eighth step is made, the roller 23 of switch 24 drops offthe opposite end of cam 21 and breaks the circuit through signals 73 and75 and at the same time the end of the companion cam, in alinement withthe end of cam 2 1 off which the roller of switch 24 drops, comes intoengagement with the roller 23 of switch 25 and raises the latter untilits contact 29 engages contact 30 in circuit with plate 37. As a resultof the breaking of the circuit throughsignals 73 and 75 magnet 74 isdemagnetized and armature 65 is retracted and makes contact with posts64 and 66. The raising of switch 25 completes a circuit through trolleywire 43, conductor 70, switch 25, and conductor 76 to ground conductor72, the current of course passing through the safety signal lamps 77,electro-magnet 78, and danger signal lamps 79 so that said signals 77and 79 are operated the instant signals 73 and 75 cease to operate, thedanger signal 79 warning any additional cars from entering the blockfrom the same end as those already therein, energization of magnet 78attracting armature 60 and breaking the circuit through post 59 and 61so that an additional car entering from said end would do so in the faceof the warning and would not affect the signal because of the break inthe circuit between posts 59 and 61. On the other hand should a carenter the block from the opposite end while the block is thus occupiedby the eight cars referred to it will reverse the signal ahead of it andthus receive warning to back out of the block onto its own track. Itreverses the signal because armature makes connection between posts 64and 66 so that the circuit is as follows: trolley wire 41 throughtheconducting appliance, conductor 63, post 64, conductor 65, post 66,conductor 67, through the relay 3, lamps 69 and conductor 68 to theground, this circuit energizing relay 3, which attracts its armature 5and thereby operates the lever 6 connected thereto and pawl 12, whichpawl engages ratchet wheel 20 and rotates shaft 16 one step oppositelyto the direction in which it was rotated by the energization of magnetor relay 2. The rotation through pawl 12 therefore causes cam 21 torelevate switch 24 and cam 22 to permit switch 25 to drop back to itsoriginal position, the completion of the circuit through switch 24 ofcourse operating the danger signal in front of the car entering or aboutto enter the block, it being understood of course that the signals areso arranged that the motorman of the car may see them before the caractually reaches the single track for the purpose of avoiding thepossibility of such car coming into collision with oppositely travelingcars on the single track, it being likewise understood that, as in thisinstance, the last of nine cars traveling in the same direction, willalso see the danger signal at his end of the block before he actuallyreaches the single track.

It will thus be seen that with fifteen teeth on the ratchet wheels,eight cars traveling in the same direction can occupy the block at thesame time, the first one entering operating the safety signal at the endof the block, entered, and danger signal at the opposite end, the lastone of the other seven cars reversing the signals in the same mannerthat they would be reversed by a car entering the block from theopposite end. If only one car occupies the block, it restores thesignals to normal condition as it passes out of the block, the circuit,in the event of the car traveling in the direction indicated by thearrow, being completed from the trolley wire 43, through conductor 80,relay 3, lamps 69 and conductor 68 to ground, the energization of relay3 rocking shaft 16 back the step which it was advanced when the carentered the block, it being understood that when the signals are normalor dead both switches are down so that the circuits through the signalsare broken. A car leaving the block from the opposite end will completea circuit from the trolley wire 44, 81, 62, relay 2, lamps 69 andconductor 68 to ground and thus cause shaft 16 to be rotated backwardthe same distance it was rotated forward when the car entered the blockfrom the opposite end.

In Fig. 11, 85 indicates the trackway of 65 the block and at theentrance thereof are short plates or equivalent devices 86, 87, and atthe exit ends similar conductors 88 and 89. The conductors are connectedrespectively to wires 58, 63, 80 and 81 and each car, not shown, has itstrolley electrically connected in any suitable manner, indicated at 90,to the brush 91 to engage the proper contact plate as the car passes andthus complete the circuit through the connected relay as described, thedrawing showing the connection at the lower left hand corner of Fig. 11with the car traveling in the direction indicated by the contiguousarrow.

In Fig. 12 a third rail system is shown, the third rails being numbered92 and 93. On both the tracks by preference are plates 94 and 95 at theentrance ends of the block and 96 and 97 at the exit ends of the block,and said plates are respectively connected to conductors 58, 63, 80 and81, and each car is adapted to be electrically connected as for instanceat 98, with the third rail, and is provided with a brush 99 to engagethe plate in its path as the car passes the latter and thus establish anelectric connection between the third rail and the wire 58, 63, 80 or81, as the case may be, as and for the purpose hereinbefore explained.It will thus be seen that this block signal can be adapted for use inconnection with a trolley system in which the cars are provided withbrushes to engage the plates 86, 87, 88 or 89 or with a third railsystem.

From the above description it will be apparent that I have produced anelectric block signal system possessing the features of advantageenumerated and Iwish it to be understood that I do not desire to berestricted to the exact details of construction shown and described asobvious modifications will sug gest themselves to one skilled in theart.

Having thus described the invention what I claim as new and desire tosecure by Letters-Patent, is

1. In an electric block signal system, a pair of contacts, a pair ofswitches therefor normally out of engagement with their respectivecontacts, and means to operate with a step by step movement and advanceone of the switches into engagement with its contact with the first stepand on a subsequent step effect the simultaneous withdrawal of theadvanced switch and the advance of the other switch into engagement withits respective contact.

2. In an electric block signal system, a pair of contacts, a pair ofsegmental cams, a pair of switches engaging the cams and adapted whenthe latter occupy their normal positions to be out of engagement withthe contacts, and means to operate said cams simultaneously with a stepby step motion to cause one of them on its first step to move itsrespective switch into engagement with one of the contacts, and on asubsequent step to effect the simultaneous withdrawal of such switch andthe movement of the other switch into engagement with the other contact.

8. In an electric block signal system, a pair of contacts, a pair ofsegmental cams, a pair of switches engaging the cams and adapted whenthe latter occupy their normal positions to be out of engagement withthe contacts, a relay, means to energize the same at intervals, andmeans caused by each energization of said relay, to operate said camssimultaneously with a step by step motion to cause one of them on itsfirst step to move its respective switch into engagement with one of thecontacts and on a subsequent step to effect the simultaneous withdrawalof such switch and the movement of the other switch into engagement withthe other contact.

4. In an electric block signal system, a pair of contacts, a pair ofsegmental cams, a pair of switches engaging the cams and adapted whenthe latter occupy their normal positions to be out of engagement withthe contacts, a pair of relays, means whereby the energization of one ofthem shall impart rotary movement to the cams to cause one of them toadvance its respective switch into engagement with one of the contacts,and means whereby the energization of the other relay shall reverse suchoperation of the cams and effect the withdrawal of the advanced switchand upon a second energization shall advance the companion switch intoengagement with its respective contact.

5. In an electric block signal system, a pair of contacts, a pair ofsegmental cams, a pair of switches engaging the cams and adapted whenthe latter occupy their normal positions to be out of engagement withthe contacts, a pair of relays, means whereby the first energization ofeither of said relays shall rotate said cams and advance the switchengaged with one of them in engagement with its respective contact andits last energization shall effect the withdrawal of said switch and thesimultaneous advance of the companion switch into engagement with itsrespective contact, and means whereby the first energization of theother relay shall effect the withdrawal of the second switch from itscontact and the rengagement of the first switch with its respectivecontact and the last energization of said relay the withdrawal of thefirst-named switch from engagement with its respective contact.

6. In an electric block signal system, a pair of contacts, a pair ofswitches therefor normally out of engagement with their respectivecontacts, means actuated by a car to advance one of the switches intoengage- ,ment with its respective contact and adapted to be actuated bya subsequent car traveling in the same direction to effect thewithdrawal of said switch and the simultaneous advance of the otherswitch into engagement with its respective contact.

7. In an electric block signal system, a shaft suitably journaled, asegmental cam rigidly mounted thereon, a contact, a switch engaging thecam, a circuit including a live conductor, danger and safety signals atopposite ends of the block and said switch and contact, a second circuitincluding said liveconductor, a conducting appliance, and a relay, athird circuit including said live conductor, a conducting appliance anda relay, means carried by a car for successively completing the secondand third circuits as it enters and leaves the block respectively, byestablishing electric connection between the live conductor and saidconducting appliances, instrumentalities actuated by the energized relayof the second circuit to rotate said shaft in one direction and causethe cam to operate the switch and complete the first circuit throughsaid signals, and instrumentalities actuated by the energized relay ofthe third circuit to reverse the operation of said shaft and effect thewithdrawal of said switch and the breaking of the circuit through thesaid signals.

8. In an electric block signal system, a shaft suitably journaled, asegmental cam rigidly mounted thereon, a contact, a switch engaging thecam; a circuit including a live conductor, danger and safety signals atopposite ends of the block, an electro-magnet and said switch andcontact; a second circuit including said live conductor, a conductingappliance, a yieldiugly-retracted armature for said magnet, and a relay;a third circuit including said live conductor, a conducting applianceand a relay; means carried by a car entering the block for establishingelectric connection between the live conductor and the conductingappliance of the second circuit, instrumentalities actuated by theenergization of the relay of said circuit to rotate said shaft apredetermined distance to cause its cam to operate the switch andcomplete the circuit through the signals and its energized magnet andbreak the second circuit by the attraction of said armature,instrumentalities actuated through the completion of the third circuitby the car and the consequent energization of the relay of said thirdcircuit to reverse the operation of the shaft to cause said cam toeffect the withdrawal of said switch to break the circuit through thesignals and said magnet.

9. In an electric block signal system, a shaft suitably journaled, apair of segmental cams rigidly mounted thereon with one end intransverse alinement and the opposite end at opposite sides of a planeextending from their transversely alined ends through the axis of saidshaft, a pair of contacts, a pair of switches having portions adapted attimes to project into the paths of said cams at the opposite side of theshaft from the alined ends of the cams; a circuit including a liveconductor, danger and safety signals at opposite ends of the block, oneof said switches and one of said contacts; a second circuit includingsaid live conductor, a conducting appliance, and a relay; a thirdcircuit including said live conductor, a conducting appliance and arelay; means carried by a car for successively completing the second andthird circuits as it enters and leaves the block respectively, byestablishing electric connection between the live conductor and saidconducting appliances; instrumentalities actuated by the energized relayof the second circuit to rotate said shaft in one direction and causeone of said cams to operate its switch and complete the first circuitthrough said signals, instrumentaliti'es actuated by the energized relayof the third circuit to reverse the operation of said shaft and efiectthe withdrawal of said switch and the breaking of the circuit throughsaid signals; danger and safety signals connected to the ground and tothe other of said pair of contacts and located at opposite ends of theblock, the danger signal being disposed at the same end as the safetysignal of the first-named signals, and a fourth circuit including thelive conductor, the relay of the third circuit and a conductingappliance at the same end of the block as the conducting appliance ofthe third circuit; said fourth circuit being adapted to be completed bythe entrance of a car into the block traveling in the opposite directionto the first-named car and thus effect a second reverse step of thesecond cam and the operation of the second set of signals.

10. In an electric block signal system, a shaft suitably journaled, apair of segmental cams rigidly mounted thereon with one end intransverse alinement and the opposite end at opposite sides of a planeextending from their transversely alined ends through the axis of saidshaft, a pair of contacts, a pair of switches having portions adapted attimes to project into the paths of said cams at the opposite side of theshaft from the alined ends of the cams, a circuit including a liveconductor, danger and safety signals at opposite ends of the block, oneof said switches and one of said contacts; a second circuit includingsaid live conductor, a conducting appliance, and a relay; a thirdcircuit including said live conductor, a conducting appliance and arelay; means carried by a car for successively completing the second andthird circuits as it enters and leaves the block respectively, byestablishing electric connection between the live conductor and theconducting appliances; instrumentalities actuated by the energized relayof the second circuit to rotate said shaft in one direction and causeone of said cams to operate the switch and complete the first circuitthrough said signals, instrumentalities actuated by the energized relayof the third circuit to reverse the operation of said shaft and effectthe withdrawal of said switch and the breaking of the circuit throughsaid signals; danger and safety signals connected to the ground and tothe other of said pair of contacts and located at opposite ends of theblock, the danger signal being disposed at the same end as the safetysignal of the firstnamed signals; a fourth circuit including the liveconductor, the relay of the third circuit and a conducting appliance atthe same end of the block as the conducting appliance of the thirdcircuit; said fourth circuit being adapted to be completed by theentrance of a car into the block traveling in the opposite direction tothe first-named car and thus effect a second reverse step of the secondcam and the operation of the second set of signals; and a fifth circuitincluding the live conductor, the relay of the second circuit and aconducting appliance and adapted as the last-named car passes out of theblock to establish connection between said live conductor and thelast-named conducting appliance to cause the relay of the second circuitto operate the shaft one .step in the same direction as the first stepand thus break the circuit through the second set of signals.

In testimony whereof I affiX my signature, in the presence of twowitnesses.

WILLIAM J. MURRAY.

